1. Field of the Invention
The present invention relates to a device for indirect application of a liquid or viscous medium onto a moving material web, specifically a paper or cardboard web.
2. Description of the Related Art
Devices for indirect application of a medium onto a moving web are known, for example, from German Patent Documents DE 43 02 435 A1 and DE 42 43 518 A1. The units described in these two documents utilize spreading rolls in processing the still moist coating layer in order to smooth surface roughness from the coating layer. Such surface roughness occurs due to the so-called "film-splitting" effect when the material web separates from the transfer element. In order to achieve the spreading movement, these spreading rolls, which are mounted transversely to the material web, are driven rotationally around their axis. Due to an additional drive, the spreading rolls perform an oscillating movement. The necessity of having to combine the movements of the spreading rolls conforming to two degrees of freedom of motion leads to a structurally expensive design in the known applicator unit. The movement necessary to position the leveling device to the material web, and the drive mechanism necessary to produce this movement, had not even been considered yet.